Conventionally, a mechanical lift facility allows passengers, skiers or pedestrians to go up or down slopes. A mechanical lift facility usually has two end stations, a station located downslope and a station located upslope. These end stations are connected by an aerial carrier-tractor cable which may form a closed loop. It is known to drive the cable by means of pulleys and to support it using pylons. Cable-suspended vehicles allow passengers to be conveyed from one end station to another.
There are several types of mechanical facility, such as chair lifts, ski-lifts, gondolas or cable cars. A chair lift-type mechanical lift facility allows passengers to go up or down a slope, in a sitting position, by means of seats suspended from a continuously moving cable.
When the cable forms a closed loop, each end station may include a passenger boarding area and a passenger disembarking area. The mechanical lift facility makes it thus possible to simultaneously transport passengers going up and down the slope.
Conveying passengers up and down a slope requires meeting a high level of security. In particular, the seats travel at a relatively large distance from the ground. It is known to improve passenger safety by using a guard rail to limit the risk of accidental falling of a passenger from the seat.
Guard rails are conventionally pivotally mounted relative to the seat to allow passengers to board and disembark. The guard rail may be in a lowered operating position or in a raised operating position. When the guard rail is in a lowered position, it constitutes an obstacle to tilting of a passenger in a vacuum. This lowered position of the guard rail is usually adopted during a phase path of the seat outside boarding and disembarking areas. When the guard rail is in a raised position, it opens up the space at the front of the seat to allow passengers to settle on the seat or leave it. The guard rail is thus normally in a raised position when the seat is in a boarding or disembarking area.
For security reasons, the guard rail must not be raised during the entire phase path outside the boarding and disembarking areas. It is, thus, known to provide the seats with means for locking their guard rail in the lowered position.
However, most means used to lock the guard rail are of the mechanical type and often require a complex structure. Consequently, said locking means do not always offer the possibility to be mounted on preexisting seats. In addition, they sometimes require substantial maintenance and can significantly weigh down the seat to which they are fitted, which often leads to premature wear of the seats and mechanical lift facilities to which they are fitted.